sample preparation stuffed up?

Judging from the description of the sample preparation methods, something has gone very wrong at the assay labs. I can't believe what I am reading (from page 9).

"SGS Minerals Townsville Sample Preparation.


Samples where the Native Copper grain size is less than 2mm were disc ground to approximately 180 (microns). 500g is then cut from the sample and lightly pulverised for 30 seconds to approximately 100 microns.


Samples where Native Copper grain size is greater than 2mm were put through a rolls crusher to approximately 3mm. Samples were sieved at 2mm with copper greater than 2mm hand picked out of sample. Material less than 2mm and residue above 2mm was disc ground to approximately 180 (microns). 500g is then cut from the sample and lightly pulverised for 30 seconds to approximately 100(micron)."

Native copper can't be disk ground to any significant extent. Copper is very malleable (including all native copper I have ever seen or heard about). From experience with disk grinders, pulverisers and roll crushers, malleable metals (such as gold and copper) dont significantly reduce in grain size, they just compact and roll up into prills.